Firefighters were still battling small fires Friday, after working through the night to put out the main blaze, state media reported.Drone footage from the country’s emergency management ministry shows an industrial area outside Yancheng city in Jiangsu province covered in firefighting foam, with storage tanks turned to twisted metals and charred factory buildings with roofs torn open.

Local authorities said earlier that dozens of fire trucks and hundreds of firefighters rushed to the scene after the blast was reported around 2 p.m. Thursday. The explosion was powerful enough for the seismological bureau to detect a small earthquake in the area, according to state media.